Adex is an ai
Arimidex (Anastrozole) : This is a widely used type II AI. It competes with estrogen for the aromatase enzyme. This effectively lowers estrogen up to 80% in the blood. Approved for use in 1995 to fight breast cancer. At doses up to 1mg a day, it has been shown to be very effective at controlling estrogen while on cycle or in PCT. It is usefull for curbing the effects that come with aromatizing AAS's while in cycle, and can be used in PCT. Nolvadex is shown to decrease the effectiveness of Arimidex when used together. In this case a suicide inhibitor may be more well suited, like in PCT. It is also called L-dex, in its liquid form.
AI's (Aromatase Inhibitors) : There are 2 types of AI's. Type I (suicide inhibitor) attaches to the aromatase enzyme and permanently disables it. Type II compete for the enzyme, but dont destroy it. Both are effective at lowering estrogen substantially. Both are commonly used during both cycling and PCT. Used mainly when low estrogen levels are desired, like contest preparation/cutting. Beware that lowering estrogen with strong AI's can have a negative effect on cholesterol levels and low estrogen levels can lead to sore joints, cause your losing estrogens anti-inflammitory effect. Can also have a negative impact on your libido. Estrogen has an important role in mass building and joint health, as noted below where "estrogen" is explained.
HCG (Human Chorionic Gonadotropin) : HCG is a replacement for your natural LH (luteinizing hormone). LH is what your body produces to tell your testicles to produce natural testosterone. LH levels drop when using AAS (HPTA suppression). Using HCG while on cycle prevents testicular shrinkage, speeding PCT when the time comes. Using Nolva while using HCG helps stop HCG from de-sensitizing your testicles to natural LH. In my opinion, any decent cycle/PCT should include HCG. It has been suggested to me that HCG can be used throughout a cycle at 500iu E4D, but im unsure of this from practical experience. The most favorable way is to use it in the last couple weeks of your cycle at a higher dose, like 500iu ED. The trick is to end the use of HCG just as the last AAS is running out of your system. So, 3 weeks before the the last ester leaves your blood, you would start the HCG/nolva combo. HCG at about 500iu ED and Nolva 20mg ED. This is done before Nolva/aromasin (for example) PCT starts, and runs about a few weeks longer than the end of the HCG. Always include Nolva with your HCG, they work together well. Be careful not to overdose on HCG and permanently desenstize your testicles to LH. HCG has an active life of about 3 days
Nolva and clomid are serms
Nolvadex (Tamoxifen Citrate) : Nolvadex is a SERM. It selectively binds to certain estrogen receptors, effectively blocking the estrogen and stopping unwanted sides such as gyno. It DOES NOT lower estro levels in the blood, it only blocks it from binding to certain receptors. It also helps your blood fat levels. It does not suppress LH, blocks desired estro receptors and helps stop HCG from desensitizing your testicles to natural LH. Nolva should be used during HCG therapy, at 20 mg a day, for the reason i just mentioned. Can be used during cycle if you see signs of gyno. Its mainly used to block the estrogen spike when you come off cycle, and should be used right through to the end until natural test levels are back. One drawback to consider about Nolva is that it may cause progesterone receptors to become more sensitive. This means that while using progestins such as Deca or Tren, you may become more sensetive to progestin related gyno.
Clomid (Clomiphene Citrate) : This drug is also a SERM, almost identicle to Nolva. It is said to be a weaker blocker mg for mg than Nolva. Its common use is in PCT, usually for about a month, used after HCG and all AAS esters have run out of your body. Even though it is weaker than Nolva at blocking, it is believed to be quicker at bringing HPTA back to balance. Both are commonly used during PCT. It binds to different receptors than Nolva. There is a lot of debate on this, but until there is solid proof, it may be prudent to include this in your PCT.
SERM's (Selective Estrogen Receptor Modulator) : These block certain estrogen receptors, ***ending on the drug, and dont actually lower estrogen in the blood. Estrogen is left to circulate with nowhere to go. Because of this, SERMS have a positive effect on cholesterol levels. They have a negative effect on IGF-1, so if bulking, only take them if totally necessary. They are good at blocking gyno. Commonly used during PCT, and less often used while cycling. A SERM like nolvadex is widely used in PCT to help kickstart the HPTA back to normal function, in conjunction with other beneficial drugs. To learn how this works, please refer to Anthony Roberts PCT in the PCT section.
They do different things. So no you can't switch nolva/clomid for adex and hcg